Question

I’ve got a Python 2.7 program that imports win32clipboard. I tried to freeze it with cx_Freeze 4.2.3 on Windows XP SP3 32-bit, to create an installation MSI. I made a setup.py according to the cx_Freeze documentation, and used the following command:

c:\python27\python.exe setup.py bdist_msi

When I run it on another PC that doesn’t have Python 2.7 installed, I get an exception on the line that imports win32clipboard:

ImportError: DLL load failed: The specified module could not be found.

I can see that win32clipboard.pyd is being included in the build.

What dependency is missing, and how can I ensure it is included?

Answer 1

I eventually figured that win32clipboard.pyd is being included, however, win32clipboard.pyd depends on pywintypes27.dll, which cx_Freeze is not copying from c:\windows\system32.

The short-term hack is to manually copy c:\windows\system32\pywintypes27.dll into build\exe.win32-2.7, then run setup.py bdist_msi again.

An improved hack is to use the following in the setup.py:

import os
import sys
import win32api
...
pywintypes_dll = 'pywintypes{0}{1}.dll'.format(*sys.version_info[0:2])      # e.g. pywintypes27.dll
build_exe_options = {..., "include_files": [ (os.path.join(win32api.GetSystemDirectory(), pywintypes_dll), pywintypes_dll)]}
...
setup(  ...,
        options = { 'build_exe': build_exe_options, 
                    ...,
                  },
        ...)

(It would be preferable for cx_Freeze to be improved to automatically detect the pywintype27.dll dependency, but I guess that’s always a work-in-progress.)